CVE-2021-3996
- Source
- https://nvd.nist.gov/vuln/detail/CVE-2021-3996
- Import Source
- https://storage.googleapis.com/osv-test-cve-osv-conversion/osv-output/CVE-2021-3996.json
- JSON Data
- https://api.test.osv.dev/v1/vulns/CVE-2021-3996
- Downstream
- Related
- Published
- 2022-08-23T20:15:08Z
- Modified
- 2025-10-15T13:15:39.774539Z
- Severity
-
- 5.5 (Medium) CVSS_V3 - CVSS:3.1/AV:L/AC:L/PR:L/UI:N/S:U/C:N/I:N/A:H CVSS Calculator
- Summary
- [none]
- Details
-
A logic error was found in the libmount library of util-linux in the function that allows an unprivileged user to unmount a FUSE filesystem. This flaw allows a local user on a vulnerable system to unmount other users' filesystems that are either world-writable themselves (like /tmp) or mounted in a world-writable directory. An attacker may use this flaw to cause a denial of service to applications that use the affected filesystems.
- References
-
- http://packetstormsecurity.com/files/170176/snap-confine-must_mkdir_and_open_with_perms-Race-Condition.html
- http://seclists.org/fulldisclosure/2022/Dec/4
- http://www.openwall.com/lists/oss-security/2022/11/30/2
- https://access.redhat.com/security/cve/CVE-2021-3996
- https://bugzilla.redhat.com/show_bug.cgi?id=2024628
- https://github.com/util-linux/util-linux/commit/166e87368ae88bf31112a30e078cceae637f4cdb
- https://mirrors.edge.kernel.org/pub/linux/utils/util-linux/v2.37/v2.37.3-ReleaseNotes
- https://security.gentoo.org/glsa/202401-08
- https://security.netapp.com/advisory/ntap-20221209-0002/
- https://www.openwall.com/lists/oss-security/2022/01/24/2
Affected packages
Git / github.com/karelzak/util-linux
Affected ranges
- Type
- GIT
- Repo
- https://github.com/karelzak/util-linux
- Events
- Type
- GIT
- Repo
- https://github.com/util-linux/util-linux
- Events
-
Introduced0 Unknown introduced commit / All previous commits are affectedFixed
Affected versions
v2.*
v2.10f
v2.10m
v2.10s
v2.11b
v2.11f
v2.11m
v2.11n
v2.11o
v2.11q
v2.11r
v2.11t
v2.11u
v2.11v
v2.11w
v2.11x
v2.11y
v2.12
v2.12a
v2.12b
v2.12d
v2.12h
v2.12i
v2.12j
v2.12k
v2.12l
v2.12m
v2.12o
v2.12p
v2.12pre
v2.12q
v2.12q-pre1
v2.12q-pre2
v2.12r
v2.12r-pre1
v2.13
v2.13-pre1
v2.13-pre2
v2.13-pre3
v2.13-pre4
v2.13-pre5
v2.13-pre6
v2.13-pre7
v2.13-rc1
v2.13-rc2
v2.13-rc3
v2.14
v2.14-rc1
v2.14-rc2
v2.14-rc3
v2.15
v2.15-rc1
v2.15-rc2
v2.16
v2.16-rc1
v2.16-rc2
v2.17
v2.17-rc1
v2.17-rc2
v2.17-rc3
v2.18
v2.18-rc1
v2.18-rc2
v2.19
v2.19-rc1
v2.19-rc2
v2.19-rc3
v2.2
v2.20
v2.20-rc1
v2.20-rc2
v2.21
v2.21-rc1
v2.21-rc2
v2.22
v2.22-rc1
v2.22-rc2
v2.23
v2.23-rc1
v2.23-rc2
v2.24
v2.24-rc1
v2.24-rc2
v2.25
v2.25-rc1
v2.25-rc2
v2.26
v2.26-rc1
v2.26-rc2
v2.27
v2.27-rc1
v2.27-rc2
v2.28
v2.28-rc1
v2.28-rc2
v2.29
v2.29-rc1
v2.29-rc2
v2.30
v2.30-rc1
v2.30-rc2
v2.31
v2.31-rc1
v2.31-rc2
v2.32
v2.32-rc1
v2.32-rc2
v2.33
v2.33-rc1
v2.33-rc2
v2.34
v2.34-rc1
v2.34-rc2
v2.35
v2.35-rc1
v2.35-rc2
v2.36
v2.36-rc1
v2.36-rc2
v2.37
v2.37-rc1
v2.37-rc2
v2.37.1
v2.37.2
v2.5
v2.7.1
v2.8
v2.9i
v2.9v
Database specific
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